my @w = () = 1;
  print "[", @w, "]\n";               # prints: []

  my @x = (undef) = 2;
  print "[", @x, "]\n";               # prints: [2]

  my @y = (undef) = (3,4);
  print "[", @y, "]\n";               # prints: [3]

  my @z = (undef, undef) = (5,6);
  print "[", @z, "]\n";               # prints: [56]

  my $temp;
  my @z = (undef, $temp, undef) = (7,8,9);
  print "[", @z, "]\n";               # prints: [789]